Asymptomatic Muscle Metastases From Esophageal Adenocarcinoma

Abstract

A 72-year-old man initially presented with a 2-month history of severe dysphagia and a 25-pound weight loss. Endoscopy demonstrated an infiltrating mass in the distal esophagus. A biopsy revealed high-grade infiltrating adenocarcinoma with signet ring cells (Fig 1). The initial abdominal computed tomography (CT) showed a 6-cm length circumferential thickening of the distal esophagus with extension to the gastroesphageal junction and adjacent adenopathy. The chest, abdomen, and pelvis CT scans showed no evidence of metastatic disease in the liver, pancreas, or adrenal glands.At this point, the patient was referred to University of Miami Sylvester Comprehensive Cancer Center (Miami, FL) for further evaluation and treatment. An endoscopic ultrasound was performed, and the tumor was staged as T3N1Mx. Whole-body [ 18 F]fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/ CT) was obtained for further staging and demonstrated avid pathologic uptake (max, 15.8 standardized uptake value [SUV]) in the distal esophagus corresponding with the known esophageal tumor. Avid nodular uptake within left deltoid muscle posteromedial to acromioclavicular joint, peak SUV measured 6.0. Avid nodular uptake in three locations within the right gluteus maximus muscle with peak SUV was 11.8. More superiorly there was an additional nodule of uptake in the right gluteus muscle measuring 4.8, and more inferomedially there was a third nodule of uptake in the right gluteus muscle, SUV measuring 10.3. There was a focal nodular uptake in the left gluteus maximus muscle, SUV 5.5 and additional focus of abnormal uptake in the left gluteus muscle was identified just dorsal to the left ischial tuberosity, peak SUV measuring 4.3. Focal intense nodular uptake within paraspinous musculature at the level of mid-dorsal spine, SUV measured 5.2 (Fig 2).A CT-guided percutaneous biopsy of the biggest (2 cm) right gluteal lesion was performed and revealed a moderately differentiated adenocarcinoma consistent with primary esophageal cancer. The tumor cells are positive for CK7 and negative for CK20 and CDX-2 by immunohistochemistry (Fig 3). Due to the presence of multiple muscle metastases, surgery was not indicated, and the patient underwent systemic chemotherapy with oxaliplatin, docetaxel, floxuridine, and leucovorin. FDG-PET/CT was repeated after two cycles of chemotherapy and demonstrated an average of 50% decrease of SUVs in the distal esophagus as well in musculature. However, there was a new identified region within left sartorius muscle, just lateral to the femoral vessels with a maximum SUV of 4.6 (Fig 4). The patient's muscles metastasis remains asymptomatic, and the patient is receiving systemic chemotherapy.Metastasis to the skeletal muscles is very rare and represents less than 1% of all hematogenous metastases from solid tumors. 1,2,3,4 Some researchers reported only 15 cases of muscle metastasis during a 16-year period in which more than 54,000 newly diagnosed cancers were diagnosed. 5 Muscle metastases account for les...

PET/CT imaging of skeletal muscle metastases

“…In our analysis, for example, in CT is the most frequent staging investigation in oncology. However, as has been mentioned previously, some SMM, especially small lesions can be underdiagnosed on CT (24,27,30,31,(34)(35)(36)(37).…”

Skeletal muscle metastasis from signet ring cell esophageal adenocarcinoma

“…Metastatic disease to both skeletal and cardiac muscle is believed to occur through hematogenous spread of tumor, as these tissues are well-vascularized (2,11). However, a literature review of esophageal carcinomas with muscle metastases reveals a pattern of spread based on tumor histology.…”

“…Twenty-one cases, including the present report, have described esophageal cancers with skeletal muscle metastases and specified the histology of the primary tumor. Sixteen of these cases (76%) are adenocarcinomas (2)(3)(4)9,(12)(13)(14)(15)(16)(17)(18)(19)(20), whereas only five (24%) are ESCCs (1,3,21,22). By contrast, 13 cases of ESCC metastatic to myocardium have been reported (11,(23)(24)(25), but no reports of esophageal adenocarcinoma metastatic to myocardium were found.…”

Soft Tissue Metastases as the First Clinical Manifestation of Squamous Cell Carcinoma of the Esophagus: Case Report

“…Palliative techniques such as esophageal stenting with self-expanding metallic stents (SEMS) may provide symptomatic relief from dysphagia. Initial staging of esophageal cancer involves CT scanning and endoscopic ultrasound, although PET scans have been suggested to be more useful in detecting soft-tissue metastases [ 9 ].…”